Cantilever Brake Hell
 

I bought a 2009 Bianchi Volpe BOS from a Cycle shop in Seattle. On the way home while braking down hill in the rain the head tube area started shaking violently. It was dangerous and not fun.

I took the bike back in and they said it was just how cantys (mine are cane creek) worked and that I should just not use the front brake. Just not use the front brake. I wanted go violent but it's my nature to play nice for as long as possible in any uncomfortable situation. They also blamed the steel fork. Are you kidding me?

Well, they increased toe-in which made braking really soft with just a little shake. It was still not the safest of situations but it's ok.

Today however the shake returned. I'm afraid to take it back to them because I don't trust they know what they are talking about. However it would be free for them to look at because it's within the 90 day period. I'm still learning how to take care of my own bike and I'm new to cantys so can someone give me some advice? The shake is violent. Very violent. I assumed my headset was loose or something.

Other than this brake issue I love this bike. I am a fan of modern steel bikes after trying aluminum/carbon modern bikes and a few vintage steel bikes. But I live in hilly and wet area and have already taken the bike on an 85 mile ride in addition to daily commuting.

First, find another shop.

Second, some canti's can be more prone to shudder than others. Some of it has to do with pivot tolerances, etc. Also, some pads are better than others when it comes to noise and vibration. A cheap test (and possible fix) would be to try some Kool Stop dual-compound (black/salmon) or salmon pads to see if those quiet things down. You can also try cleaning the brake tracks on the rims with isopropyl alcohol.

Lastly, if your bike has a headset-mounted cable hanger, you may want to try a fork-mounted hanger/stop. Many cyclocross racers report that those help reduce/eliminate brake noise/shudder.

Mark's pretty much got it all covered and those are the things that worked form me on my Bianchi Axis. I also found a wide brake like the Tektro CR720 to be easy to set up as powerful with no shutter.

On my latest cyclocross bike I just ditched the cantis all together in favor of mini-V brakes. The design of V-brakes eliminates brake shudder and I find them to feel better than cantis as well. You have several options for brake arm lengths and the longer the arm length, the closer you are going to have to have the pads to the rim to start with.

In other words, at 80mm bmx size mini- v brakes, you've got some gap, at 85mm like the tektro rx-5 I use it's getting close enough to require you to have nicely true rims but works fabulously for me, at 90mm pad clearance has got to be even closer but that's what the new TRP V-brake arms are so it's got to still work fine, and then anything over 90 or 95mm you're getting into the regular v-brake length and so with road brake levers you'll need to use one of those "Travel Agent" adapter pulleys at the front noodle. (nothing wrong with using that).

It wouldn't cost you much at all to get a front mini-v brake and koolstop pads and probably a new front brake cable and housing. Just leave the rear canti brake on if you want.

I take it V brakes use the same mounts as cantis?

I have a very large frame so the fork mount may be a good idea. The wire going from the mount to the brake is very long.

Yes, V-brakes mount to the fork the same as cantilever brakes. But with your large frame, I bet you'll find good results going with the fork mounted cable stop instead of the one up at the stem. You'll just need the mount and a new brake cable housing and cable to try it out.

Check the following:

1. front-wheel bearings, some lateral-play between brake-pads when QR is barely on. No play when QR fully tightened.

2. head-set bearings. While standing on side of bike, squeeze front-brake and push handlebar back and forth. Movement here can also show front-wheel bearings, so do #1 first

3. rim clean? Use some acetone to wipe down both sides. Oil and grease really isn't visible on the braking-surface, but can lead to slippery spots that cause shuddering

4. brake pads clean? Wipe those down as well, and pick out any metal. Maybe even lightly sand them with 200-grit sandpaper to remove any smoothness

5. RIM-WIDTH, use calipers to measure the outside width of the rim. Slide the caliper along the rim to see if it catches anywhere along the way. Impacts into potholes, speed-bumps, etc. can cause pinched-flats, and also spread out the rim sidewalls a little, leading to grabbing and shuddering brakes.


And yes, find another shop. Their responses are very shady, leading me to think that they know about a pre-existing condition on that bike.

The flexing of the fork from the pivots upward to the cable hanger , changes the tension that is pulling the pads to the rim.

It's a mechanical feedback loop , like theacoustic one you hear when at a loud rock concert and the sound system's speakers
is heard by the microphones in that sound system

Yes a V brake will be better as its just the cable, directly pulling the arms together.
need different levers that pull more cable.

I'm going to try the fork mount first and then do the standard things DannoXYZ is suggesting. Thanks all.

To not confuse the OP, with mini-v brakes you do not need new levers since they work fine with typical road bike levers. And even if using a full size V brake, one can still use the road levers if he attaches a "travel agent" pulley at the v-brake noodle that increases the cable pull. Much cheaper solution than changing levers and shifters and all that jazz.

I have Tiagra brifters that are supposed to work with cantis and v brakes.

WTF********** Did they really say this???

I'd start by changing the front brake pads. Stock pads usually aren't the greatest when it comes to quiet operation and good control.

These are all great responses, but if I were in that spot, I would go back and tell them to fix the problem or refund the cash.

Yes. Don't use the front brake. I'm going back there today to get the fork mount thing. They are going to charge me to remove the headset one. I'm going to leave it there and see if they will take it out during my full 90day 'tune up'. Otherwise ill remove it myself so I never have to go back to this place.

Such a good reminder that you never buy a bike. You buy a local bike shop. Choose wisely.

Some thoughts: I've run the cane creek scx canti brakes. They're not exactly awesome, but they do not cause the situation you've described. Similarly, a stem-mounted cable hanger, even in conjunction with a very long headtube, will not cause such shaking either. I suspect that your headset is loose, but it may be related to front wheel bearings or perhaps some other, more nefarious issue i'm not aware of.

That shop sounds terrible. Go in, ask for the head honcho/honcha, and ask him/her to take a testride on your bike. After, explain to him/her that you're not foolish enough to believe that bianchi or any other reputable manufacturer would spec brakes and forks that cause this sort of occurrence. Explain that, even if they did, you cannot believe that a reputable dealer would stock such a bike, sell it to a customer for about a grand, and then play stupid when he comes in and complains.

Tell him/her about the advice his employees gave you, and demand that you get a bike with a working front brake/properly adjusted headset/no terrible issues, or a refund.

Play tough with these scoundrels, pronto.
-rob

ps-i think volpes are nice.

Your LBS may not have known exactly how to solve the problem but the advice they gave you was close to criminal negligence.

Your problem is fairly common on canti-equipped bikes, particularly if the front cable hanger is mounted on the headset. Lennard Zinn did an extensive column on the Velo News web site about this problem and it's cure. Here is the reference. Basically, the conclusion is to mount the cable hanger on the fork crown if at all possible.

http://velonews.competitor.com/2010/...o-cross_101807

BTW, I have a Surly Cross Check with Shimano BR-R550 cantis with the cable hanger mounted just above the headset's top bearing cover and they never shudder at any speed or level of application. However, the Surly has a 1-1/8" steel steerer so it's a lot stiffer than any carbon steerer and that helps a lot.

Is this one of those bikes that has the cable stop built into the stem? The solution I've heard for this, is to switch to a cable stop that mounts near the fork crown. That bypasses the flex in the steerer and stem that causes the shuddering.

I've never had a problem with canti shudder, and I've had plenty of bikes with the cable mount on the headset. Then again, they've all been steel frame mountain bikes.

Your "shop" gave you the most ridiculous answer ever. Can you still return the bike? I would if possible, and then go buy the exact same bike elsewhere. Not just because of this problem, but because of how worthless they must be to tell you something like that.

worthless? might be

I have 2 steel road bikes (both Surly) with cantilever brakes. Older one is 5 years and has around 12,000 miles. My wife as 2 ,more. The brakes work normally. Could be your front wheel is out of line. Maybe the problem is in the head set or front hub, or maybe your fork is slightly out of line. But you and I should not have to diagnose this problem on a bike under a year old. I suggest you take it back to the shop one more time and tell them politely but very firmly that you expect them fix it so the problem goes away entirely (and a loaner to ride while they work on it), give you a new bike, or return your money.

If they don't come through, don't take chances with your life. The bike sounds like it could be dangerous in some situations. Take it to another shop, pay them to take care of it and present the bill to the seller. If they don't pay, sue them in small claims court.

Any advice to not use the front brake is coming from an idiot; most of your braking comes from the front brake.

My Bianchi Castro Valley frame (similar to the Volpe) had this problem when I first built it up. I didn't have the bolt that holds the spacer and stem stack down tight enough. There was enough play in the system to make steep descents on a century ride VERY exciting (enough that after the 1st time, I was manic about keeping my speed down regardless of how many folks were passing me). I was left with loud brake squeal on the fronts (useful for unambiguous warning of ninja joggers on my commuting route but annoying to me). Fix was combination of cleaning rims and pads, and switching pads. KoolStop salmon pads were quieter and have excellent (for me at least) braking. Currently trying some Velo Orange no-squeal pads; they are QUIET but don't seem to provide as much stop in dry conditions; waiting for another wet commute (we're having a dry spell here) to see how they work with wet rims.

BTW, I love the Bianchi steel frames - plenty of places to mount stuff, the forks take nice wide tires AND fenders (ran 35mm studded last winter), and celeste is a great color for a bike IMO.

The advice w/ respect replacing the shop is spot-on. It isn't only about not knowing how to solve the problem, but knowingly selling a bike when they feel the front brake shouldn't be used. They need to either know how to make it work, replace it, or sell other bikes. I can't see any way I'd excuse the way they do business.

Now to solving your problem. Replacing the shoes may help, along with proper (1/16") toe-in. Changing the cable hanger to a stiffer one may also help.

It also helps to understand the root cause of the problem, which is that the froward motion of the rim pushes the shoes forward exerting a twisting force that brings the toes out. It's compounded on cantis because the force of clamping pushes the pivots out, which again tends to push the toes out. Bringing the toes out brings the heels in, causing the corners to dig in and vibrate much like new chalks screeches on a blackboard. Like with chalk, part of the solution is to dull the back corner. You can see the flex and tendency to toe-out by applying the brakes gently, and pushing the bike forward against them.

So, here are a few things you can do.

1-remove the wheel and use a file to break the back corner and form a small radius, or a ski tip shape, so it won't dig in when applied
2-see if you can find thin washers to reduce the free play on the brake arms on the pivots.
3-install a brake booster on the front brakes to stiffen the assembly so that the bosses can't flex apart under load. Some brake boosters also include a cable hanger which will fill the needs of Mr. Zinn's solution. I'd insist the shop install the booster at their expense (or Bianchi's) if they can't get the brakes working to a reasonable standard other ways.
4-this doesn't always work, but I've found that using a stiff grease when fitting the brakes to the posts tends to dampen vibration, but it only works if the brake return springs are strong enough.

BTW- the reason that rear brakes don't have the problem is that their bosses point backward, so the brake pressure brings the heels out, nicely offsetting the effects of the forward motion of the wheel.

I got the fork mount/stop and the problem is gone. They did charge me for installation even though they said they weren't going to. The bike was a 2009 NOS $799 and my size so I didn't want to take it back. After my 90 day free tuneup I'll never walk in the place again. I have 3 much better options (Recycled Cycles, Free Range Cycles, and Wright Brothers) all in my area. Not to mention I'm taking the maintenance classes at Wright Bros soon I shouldn't need service anyway.

Glad to hear that the fork-mounted cable stop solved the problem.

When you're comfortable doing your own maintenance, think about replacing the stock pads. Even the plain black Kool Stop pads stop better than most stock brake pads.

Thanks for the responses. I really tried to give Gregg's Cycles one more shot but I just can't. The place is a breeding pit for *******s and morons. I will be actively telling my friends never to go there.